We create MNIST/STL-10 by overlaying MNIST [1]} handwritten digits on STL-10 [2]} images. Each overlayed MNIST image is centered at one of eight possible pixel locations in the STL-10 image (Figure REF ). Since MNIST digits tend to saturate each color channel, a simple per-pixel maximum of the MNIST digit image and the STL-10 image was used. An MNIST/STL-10 instance is generated by specifying three properties: 1) the MNIST digit instance belonging to one of 10 classes (0 - 9); 2) the STL-10 instance belonging to one of 10 classes (airplane, bird, car, cat, deer, dog, horse, monkey, ship, truck); and 3) the pixel location at which to center the MNIST instance on the STL-10 instance (8 possible values).
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